The use of wheelchairs is well known and widely practiced. Wheelchairs are normally propelled by the user with the user gripping and pushing on a circular member or hand wheel which is attached to the outside of each rear wheel. Normally, the circular member is of a diameter slightly smaller than that of the wheel. There is a direct connection or drive from the hand wheel(s) to the wheel or wheels of the wheelchair.
Typically, people using wheelchairs can include those of any age who have suffered an injury to the lower body which prevents walking or at least renders the same uncomfortable. Also, a number of elderly people who do not have the requisite leg strength to stand and/or walk use a wheelchair on a regular basis.
Getting into and out of a wheelchair can prove to be a highly risky operation. In order to do either, the wheelchair user should engage a brake on the wheelchair to prevent the wheelchair from moving during the seating or unseating process. New users of wheelchairs and even some people who have used wheelchairs for a period of time occasionally forget to activate the brakes on the wheelchair. When rising, the weight transfer to the arm rest when trying to stand up will often cause the chair to move rearwardly which then puts the person off balance, resulting in a fall. It goes without saying that such falls can be highly dangerous and particularly for people already suffering from an injury and/or disease.
There are wheelchairs which are manufactured and which incorporate devices to prevent the movement of the wheelchair. Such devices can be disadvantageous for differing reasons.